Air conditioning apparatus



May 12, 1942. E. R. WOLFERT AIR CONDITIONING APPARATUS Filed Dec; 1,1938 2 Sheets-Sheet 1 CQNDENSEE INVENTOR E. E. WQLFEET. BY

ATTORN WITNESSES: 7 7

y 942. E. R. WOLFERT I 2,283,024

AIR CONDITIONING AP PARATUS WlTNESS| ES: v I INVENTOR 7? I 5 -WOLFR.T.

.2 63 W W UATTORY Patented MayQIZ, 1942 r Edward R. Woli'ert,Springfield, Mass.,

assignor to Westinghouse Electric & Manufacturing Gompany, East Pittsbof Pennsylvania urgh, Pa., a corporation Application December 1, 1938,Serial No. 243,410

1 Claim.

. My invention relates to a motor-compressor unit for a refrigeratingsystem, more particularly to a unit enclosed in a fluid-tight casing andwherein the motor is cooled by the expanded refrigerant vapor flowing to'the compressor, and it has for an object to provide an improved unit ofthe character set forth.

A more particular object is to provide an improved arrangement forseparating oil from the expanded refrigerant vapor before the sameenters the compressor cylinders.

In accordance with my invention, the motor housing, through which theexpanded refrigerant vapor flows in contact with the motor for coolingthe same, is formed to provide sufficient change in direction of flowand sufficiently low velocity to permit the lubricant entrained in therefrigerant vapor to separate therefrom by gravity, so that the motorhousing serves as an ,oil separator. In the horizontal unit, the motortor-compressor unit, wherein the housing is formed with a vapor outletwhich is located, preferably at the top of the motor housing and remotefrom the vapor inlet, so as to receive refrigerantvapor from which theoil has been separated. The refrigerant vapor is then admitted to thecompressor cylinders.

These and other objects are effected by my invention as will be apparentfrom the following description and claims taken in connection with theaccompanying drawings forming a part of this application, in which:

Fig. 1 shows diagrammatically a refrigerating system incorporating ahorizontal motor-compressor unit in accordance with my invention, theunit being shown'in vertical section;

Fig. 2 is a broken perspective view showing the refrigerant vaporpassage from the motor housing to the compressor cylinders;

Fig. 3 is an end view of the motor with the end cover plate removed, asseen on' the line III-III of Fig. 1; and 2 maintain a constant degree ofsuperheat of the refrigerant vapor leaving the, evaporator.

The refrigerating system as a whole operates in the usual manner of suchapparatus, the refrigerant gas compressed by the motor-compressor unitIt being conveyed through the discharge conduit Ii to the condenser l2,wherein the same is condensed. The liquefied refrigerant then flows tothe evaporator l4 through the 'expansion valve l3, which regulates theflow and also reduces the pressure thereof. In the evaporator It, theliquid refrigerant is vaporized by heat extracted from the substance tobe cooled bythe evaporator and the vaporized refrigerant flows throughthe suction conduit l5 to the mosame' is re-compressed and recirculated.

The motor compressor unit It includes a compressor l6 and a motor themotor are enclosed in a fluid-tight casing I8 which comprises a mainframe or casing memher l9, end cover plates 2| and 22 and a'cylinderhead 2-3. The fluid-tight casing 18 is divided by a partition 24 into acompressor housing and a motor housing. Compressor cylinders 25 areformed in the compressor portion of the main frame or casing member l9,and pistons 26 movable therein are connected through connecting rods 21to a crankshaft 28. The latter is journalled in bearings 29 and 20carried by the cover plate 2| and the partition 24, respectively.

Below the cylinders 25, the compressor'housing forms a crank case 3|,the lower portion of which constitutes an oil or lubricant reservoir.The body of 011 extends into the motor housing, the partition 24 beingformed with an opening 32 extending below and above the surface of thebody of oil. An oil pump 33 is driven by the crankshaft through gears34and has its inlet submerged in the oil. It discharges oil throughsuitable passages to the several bearing surfaces,

Fig. 4 is a perspective view of a similar motorcompressor unit having agreater number of cylinders.

. Referring to the drawings in detail, the-motor-.

compressor unit indicated generally by the reference numeral I0, is partof a refrigerating system which includes, in addition tosaid unit, adischarge conduit H, a condenser l2 which also serves as a liquidreceiver, an expansion valve 13, an evaporator 14 and a suction conduitIS. The expansion valve l3 may be of any suitable type known in the art,such as a thermostatic expansion valve which regulates the flow to as iswell known in'the art.

The motor I! includes a rotor 35 mounted on an overhung portion 36 ofthe crankshaft 28.

The motor 35 is formed with axially-extending passages 31 for flow ofexpanded refrigerant-vapor therethrough to cool the rotor. The motorfurther includes a stator 38, which is pressed into the cylindricalinner surface of the motor housing, the latter serving as a frame forthe motor. The stator 38 is formed to provide passages 39 between thesame and the motor housingfor flow of refrigerant to cool the stator.These passages may be provided by forming the stator as shown in Fig. 3,the stator being provided H. The compressor and vapor outlet 45 portion52.

with cylindrical surfaces 4! which contact the motor housing and withflat surfaces 42 which provide the passages 39.

The end cover plate 22 is formed with a vapor inlet 43 connected to thesuction conduit, 15. A strainer 44 may be provided at the inlet asshown.

The casing member is is formed to provide a for the motor housing at thecompressor end thereof. As shown in Fig. 2, the outlet 45 is disposedadjacent the top of the motor housing and on one side of the unit. Thecasing member 19 is further formed to provide a passage 46 for flow ofrefrigerant vapor from the outlet 45 to the compressor cylinders. Thepassage 46 comprises a portion 41 extending horizontally from the outlet45 and a portion 48 extending vertically along the pair of cylinders. Iprefer to provide one passage portion 48 for each pair of cylinders, andthe horizontal portion .41 is of suflicient extent to communicate withall of the passage gtic-rtions 48.

The motor-compressor unit shown in Fig. 4 has four cylinders, so thatthe horizontal portion 41 is of greater extent.

Each cylinder of the compressor is provided with inlet and dischargevalves, the specific construction and arrangement of which forms no partof the present invention. By way of example, I show a valve cage 49clamped between the cylinder head and the cylinder, and including aninlet valve portion and an outlet valve The expanded refrigerant vaporflows from the vertical passage portion 48 through a tubular connectingmember 53, a suitable inlet chamber 54 in the cylinder head and theinlet valve portion 5| to the cylinder. The compressed refrigerant flowsfrom'the cylinder through the discharge valve portion 52, a suitabledischarge passage or chamber 55 in the cylinder head, a tubularconnecting portion 55, and other suitable passages (not shown) to thedischarge conduit H. For further description of the valve and cylinderhead construction, reference is made to Patent No. 2,134,077 of EmilEhret.

As will be noted particularly upon reference to Fig. 1, when therefrigerant vapor enters the motor housing from the inlet 43, thedirection thereof is suddenly changed, and the velocity thereof isgreatly reduced due to the relatively great amount of space or flow areain the end of the motor housing. Accordingly, the particles of oil orlubricant entrained in the refrigerant vapor have ample opportunity toseparate by gravity and to drop to the body of liquid in the bottom ofthe motor housing. The refrigerant vapor flows from the outer end of themotor housing to the compressor end through the passages 31 and 39 andthe gap between the rotor and the stator, thereby cooling the rotor andthe stator by direct contact therewith. As the refrigerant vapor leavessaid passages and said gap and enters the compressor end of the motorhousing, the direction of most of the refrigerant vapor is again changedand its velocity reduced, thereby providing further opportunity forseparation by gravity of particles of entrained oil or lubricant.Accordingly, as the refrigerant vapor reaches the outlet 45, the oil hasbeen effectively separated therefrom. The refrigerant vapor then flowsto the several cylinders through the passage 46 as described above.

From the above description it will be seen that I have provided a motorcompressor unit wherein the motor housing serves as an oil separatingchamber, thereby dispensing with the necessity of providing a separateor additional oil separator.

What I claim is:

An enclosed motor and compressor unit for a refrigerating systemcomprising a compressor, a motor for driving the compressor, a commonfluid-tight casing for the compressor and the motor, said casingincluding a crankcase for the compressor and a tubular housing for themotor extending horizontally from the crankcase and having an end wallat the end remote from the crankcase, a substantially vertical partitiondisposed between said crankcase and'said motor housing, a shaftextending horizontally through said partition for connecting said motorand compressor, said motor embodying an armature carried by said shaftand a stator secured in said tubular housing of the casing structure,said stator and said rotor being so spaced from the end wall of themotor housing as to provide a refrigerant space of substantial volume toeffect separation of lubricant by gravity from the refrigerant vapor,means provided on the portion of said casing forming said refrigerantspace for admitting vaporous refrigerant having lubricant entrainedtherein to said space, means provided in the lower portion of the casingfor conveying lubricant separated from the refrigerant to the crankcase,and passageway means provided in the casing above the oil therein forconveying refrigerant vapor from said refrigerant space axially throughthe motor to cool the same and thence to the inlet of the compressor.

EDWARD R. WOLFERT.

CERTIFICATE OF CORRECTION. Patent No. 2,2 5,o2LL. May, 12, 19b2,

EDWARD R. WOLFERT.

It is hereby certified that errors appears in the printed specificationv of the above numbered patent requiring correction as follows; Page 1,sec=- ond column, linefid, for "29 and 20" read 29 and 50-"; page 2second columh, line 22-25, after the word and period sepafa'cor. insertthe fol= lowing paragraph While I have shown my invention in severalforms, it will be obvious to those skilled in the art that it is not so11411- ited, but is susceptible of various other changes and modifications without deparolngfrom the spirit thereof, and i desire,therefore, that only such limitations shallbe placed thereupon as areimposed by the prior art or as ere specifically set forth in theappended claims. Q

in that the same may conform to the record 01' the case in the PatentOffice Sigmd and sealed this 25rd day of June, A. D. 192m,

Hom Van Az-"sdele, (5. 1) Acting Commissioner of Patents,

